Cowell, as a judge in the television's talent show Pop Idol, was so impressed by the Tom Jones impersonation that he even hinted at a possible career in pop for the Port Talbot comedian.

"OK, OK, you're going through to the next round," declared Cowell.

A modest Brydon was yesterday playing down his potential as a pop star, but his Cardiff-born agent Paul Duddridge said, "At last Rob's two great loves, Tom Jones and singing, have been recognised by the king of the music industry."

Pop Idol is at the centre of controversy after a handful of MPs condemned its judges for putting image before talent.

Seven politicians have tabled an early day motion criticising the "so-called music experts" whose comments are claimed to put out the wrong message to young fans.

Pete Waterman voiced fears at the auditions that Michelle McManus was not Pop Idol material because of her size.

However, she has made it into the final line-up along with another large contestant, Kim Gee.

MP Jim Sheridan tabled the motion, which has now been signed by nine other MPs.

"I don't think the programme does any harm," he said. "Young people are not so superficial as to try and base their lives around the programme. It's a bit of fun, it's popular and it gives people space to dream."

Mr Opik said the issue of Pop Idol was unlikely to be high on the list of Prime Minister's Questions, adding, "It could be that Jim is sore about not making it on to the programme himself."

The MPs' motion states, "That this house condemns the irresponsible comments of the so-called music experts on this programme when passing their judgements on the young performers.

"Pressurising young people and women in particular to conform to fit the mould sends out the wrong message, not only to the participants but to the other talented youngsters who may also have aspirations to progress in the music industry.

"Contestants should be judged solely on their unique singing talents and not on preconceived images.

"We therefore believe that the self-appointed image makers should break the mould which could be denying those of us who enjoy listening to quality music that opportunity."

Pop Idol producer Claire Horton hit back, saying, "Pop Idol gave Kim & Michelle the opportunity to get into the music industry despite them not having the stereotypical look of a pop star.

"If the judges were concerned about image they would not have put them through to the final 50 and the audience would not have voted them through to what is now the final eight.

"I am honoured, however, that the programme is so important that it is being discussed in the House of Commons."